class Rubytracer::PointLight
Public Class Methods
new(value, point)
click to toggle source
# File lib/rubytracer/lights/point.rb, line 5 def initialize(value, point) @value = value @point = point end
Public Instance Methods
check_shadow(point, direction, distance, scene)
click to toggle source
# File lib/rubytracer/lights/point.rb, line 10 def check_shadow(point, direction, distance, scene) ray = Geom3d::Ray.new(point + direction * 0.00001, direction) obj, alpha = scene.intersect(ray) pos = ray.pos(alpha) alpha < distance end
diffuse(normal, point, scene)
click to toggle source
# File lib/rubytracer/lights/point.rb, line 34 def diffuse(normal, point, scene) vector = @point - point dir = vector.unit dis = vector.length if check_shadow(point, dir, dis, scene) Colour.new(0,0,0) else @value * distance_loss(dis) * [0, dir.dot(normal)].max end end
distance_loss(distance)
click to toggle source
# File lib/rubytracer/lights/point.rb, line 17 def distance_loss(distance) ([0, 8 - distance].max / 8) ** 3 end
specular(normal, view_vector, point, scene)
click to toggle source
# File lib/rubytracer/lights/point.rb, line 21 def specular(normal, view_vector, point, scene) vector = @point - point dir = vector.unit dis = vector.length if check_shadow(point, dir, dis, scene) Colour.new(0,0,0) else d = (2 * view_vector.dot(normal) * normal - view_vector).unit @value * distance_loss(dis) * [0, d.dot(dir)].max end end